It would be interesting if the book is adjustable on data entries.
This will allow to make a selective research to find the right people.

For example, a group of project management setting its input data with info "area of expertise" and menu "Mechanics, Electronics, Automobile ...". Thus when the project manager have to mobilize resources on a project related to electronics, he can easily find the right people in the database. No address book does this function ...
It would be a more powerful if we can set of data entry and pull-down menus associated with selective search option.